Q&A with Dr. Hornbrook: Zirconia Bonding

Q: Do you air dry or rinse after the Ivoclean? A: Rinse. Let the Z-prime sit for 20 seconds.

Q: After a minute of Z-prime, do you air thin? How long? A: Just air evaporate. It dries quickly, less than 10 seconds.

Q: To be sure, no curing after the porcelain bonding resin? A: No curing. Place and air thin.

Q: Is Calibra catalyst+base (dual cure when mixed) okay to use as the resin cement? A: Yes, but not my favorite.

Q: Is there a reason you fill the restoration and place it in a light protective container instead of filling it right before seating the crown? A: For posterior or a single crown, I fill it and then go right to the mouth. With multiple restorations, I preload.

-MB

Q&A with Dr. Hornbrook: Esthetic Material

My good long term patient wanted to look better and we were thinking of taking off old opaque PFM and chipped composites (the PFMs were deep subgingival and hard as a car bumper). Underlying shade was not good. I warned him we may have to opaque and he seems okay with it but he picks an OM3 shade.  I have done some emax and it has covered pretty well in posterior, but the lab wants to do prismatic which is their zirconium overlaid with feldspathic. I have held the case for three days trying to decide what to do.

I have been wanting to try the esthetic zirconium’s that you showed at the seminar and I saw at the 3M booth. I take it that this is not a good case for it. If I do go along with zirconium and overlaid porcelain, are there some materials that are better esthetically than others depending on the lab? Ie lava vs glidewell vs???

-RC

Depending upon the thickness of the crowns, the new HT ZrO2, like lava Esthetic, can be a very good option.  This material can either be monolithic with staining or cutback and layered, like the Prismatic you described. In the anterior, due to esthetic demands, I would use Lava Esthetic and have it overlaid on the facial with Noritake powder-liquid ceramic. They can choose a brighter shade as a base, which will neutralize the underlying dark color, and overlay with some beautiful enamel porcelains.

You could also use E.Max as a core (they make opaque E.Max) but it is not as strong as the Lava Esthetic. Utah Valley Dental Lab has done some really beautiful ZrO2 layered Crowns, using Lava Esthetic, to cover dark preps in cases very similar to your patient. As far as ZrO2, I am not a fan of Glidewell’s Bruxzir material.  The original is just too opaque and their new Buxzir Anterior is not as translucent and vital as the Lava Esthetic.  As a second choice, I like Katana ZrO2 which is available in multiple opacities.

-Dr. Hornbrook

Q&A with Dr. Hornbrook: Primer for Temps, Veneer Cement, etc

What do you use for…

Primer (or other) painted on teeth before making anterior shrink wrap temps?

-MicroPrime G (Danville), followed by OptiBond FL Primer and air dry thoroughly.

Etch/bond combo for retention of more veneer-like temps?

-Same except spot etch in center of tooth with H3PO4.

Veneer lusting resin cement (overall):

-Variolink Esthetic.

Opaque (but not too dark or white) lusting resin cement for brightening the veneer a bit?

-Variolink Esthetic has a Light + and a Light shade 

Bonding agent for use with these materials?

-All Bond Universal (Bisco)

Thanks, CB

Q&A with Dr. Hornbrook-Bridges

Q. Am I correct  that you prefer cantilever bridge mx canine to lateral vs maryland bridge? -GB

A. Absolutely.  I do not tie a canine to a central expect as a provisional.

 

Q. Still prefer implant over both cantilever and maryland bridge? -GB

A. Implant is my first choice unless bone or soft tissue would compromise esthetics

 

Q. What material would you use on 4 unit bridge mx anterior?  -GB

A. I would use Katana ML ZrO2 overlaid on the facial with Noritake or E.Max.  Utah Valley Dental Lab has done some beautiful bridges for me in the anterior and posterior using these materials.

 

Q. I have used Procera on 3 units but have been told it is contraindicated for more than 3. -GB

A. Procera was contraindicated for bridges with more than one pontic, as are the HT ZrO2 like Lava Esthetic.

-Dr. Hornbrook

Q&A with Dr. Hornbrook-Implant Crown Cementation

Question:

I wanted to ask you what you typically use for your implant crowns cementation – specifically metal abutment to porcelain crown vs. metal abutment to PFM.

In addition, I wanted to ask you what you recommend for a particular case – I did implant supported bridges and I have a situation with this patient where one of her implant bridges keeps coming out. I’ve tried several cements with no success.

-CG

Answer:

For the anterior, I always use a ceramic custom abutment with an all-ceramic crown so I bond it into place using a light cure resin cement.  My cement of choice is Variolink Esthetic LC from Ivoclar.  For posterior implant supported crowns, I try to do screw-retained, but if not possible, I will use a resin cement.  I like TheraCem (Bisco) because I obtain good adhesion, but it is also anti-bacterial.  This cement is also my cement of choice for ZrO2 crowns.

As far as your case, the question should be “why”?  Does it fit passively? Is there a balancing or working interference that is causing stress on the cement?…  Check that first.  If the answer is not, then I would clean the abutments with alcohol, isolate, and then pace a metal-primer (Z Prime +- Bisco) on the abutments and then bond into place using a dual cure resin cement.

-Dr. Hornbrook